Field of the Invention
The present invention relates to an optical fiber fusion splicer and an optical fiber fusion splicing apparatus which is provided with the optical fiber fusion splicer.
Description of Related Art
When performing a fusion splice of an optical fiber, in general, the fusion splice is performed in the following procedure by using an optical fiber fusion splicing apparatus.
(1) An optical fiber core wire is extracted from an optical fiber cable.
(2) A resin coating (a tip) covering the extracted optical fiber core wire is removed by an optical fiber coating removal tool.
(3) Resin coating debris remaining on the surface of glass (a bare optical fiber) of the optical fiber core wire with the coating of the tip removed therefrom is removed with a cloth or paper wetted with alcohol.
(4) The optical fiber core wire which has been cleaned is cut by an optical fiber cutter.
(5) The cut optical fiber core wires are fusion-spliced by the optical fiber fusion splicing apparatus.
(6) The fusion-spliced optical fiber core wire is covered with a heat-shrinkable reinforcement sleeve and heated and reinforced by a heater of the fusion splicing apparatus.
(7) The heated and reinforced optical fiber core wire is stored in a storage tray of a connection portion storage case.
As an optical fiber fusion splicer which is used in the process (5) described above, for example, a device (a single-core machine) for fusion-splicing a pair of single-core optical fibers by discharge heating between a pair of electrode rods, or a device (a multi-core machine) for fusion-splicing end portions of a pair of multi-core optical fibers (a tape fiber) together by discharge heating between a pair of electrode rods is provided.
In the related art, as an optical fiber fusion splicer which is used for a single-core optical fiber, for example, an optical fiber fusion splicer having a function and a configuration as shown in FIG. 8 and described below is widely used.
(a) A pair of optical fibers (not shown) is illuminated with one or two illumination lamps for observation from one direction or two directions and the optical fibers are observed in one axis or two axes from the each direction by one or two lenses for observation (not shown) or one or two cameras (not shown).
(b) Glass portions (core wires) of the pair of optical fibers with coatings removed therefrom are disposed on a pair of V-grooves 121 and gripped by a pair of fiber clamps 106A and 106B for pressing the pair of optical fibers against the V-grooves 121 from above.
(c) The fiber clamps 106A and 106B for gripping coating portions of the pair of right and left optical fibers, which are movable in a longitudinal direction of the pair of optical fibers, or easily detachable fiber holders (not shown) are disposed one for each of the right and the left.
(d) A windshield cover 111 has a structure of covering a pair of electrode rods 115A and 115B, the V-grooves 121, and the fiber clamps 106A and 106B or the easily detachable fiber holders (not shown) and preventing wind from the outside from reaching the periphery of an electrode.
When fusion-splicing right and left optical fibers which are paired, by using an optical fiber fusion splicing apparatus 100 of the related art as shown in FIG. 8, in order to reduce a transmission loss of a connection portion, alignment is performed so as to precisely match the axes of the optical fibers, and thereafter, the optical fibers are advanced and fused. At this time, an operation to align the axes of the optical fibers can be performed by making tips 91a of core wires 91 of a pair of optical fibers 90A and 90B face each other with a predetermined end face distance therebetween, as shown in FIG. 3, and then finely moving the optical fibers 90A and 90B in an X-axis direction or a Y-axis direction.
As a mechanism which is used for the alignment of the optical fibers, as described above, for example, a fusion splicer 101 which is provided with an elastic alignment mechanism having an elastically deformable elastic member, as shown in FIGS. 9 and 10, is proposed. In the fusion splicer 101 shown in FIGS. 9 and 10, two plate-shaped elastic members 103A are disposed so as to extend obliquely upward from the right side of a fixed base 104 in FIG. 9, and the tips thereof are connected to a V-grooved stand 102A with a V-groove 121 provided therein. Further, similar to the above, two elastic members 103B are disposed so as to extend obliquely upward from the left side of a fixed base 104 in FIG. 9 and the tips thereof are connected to a V-grooved stand 102B with the V-groove 121 provided therein. Further, the elastic members 103A and 103B are configured so as to extend to be inclined so as to face the center in a width direction of the fixed base 104, from the front and the back in a longitudinal direction (the right-left direction when viewed from the front side of the optical fiber fusion splicing apparatus 100 shown in FIG. 8) of the fixed base 104. In this manner, the fusion splicer 101 shown in FIGS. 9 and 10 has a structure in which right and left aligning structures are integrated with each other through the fixed base 104.
Further, the elastic members 103A and 103B shown in FIGS. 9 and 10 are disposed such that two elastic members of each of the elastic members 103A and 103B are parallel to each other and the elastic members 103A and the elastic members 103B are orthogonal to each other. In this manner, the two elastic members of each of the elastic members 103A and 103B are parallel to each other, and therefore, when the elastic members 103A and 103B are elastically deformed, a pair of optical fibers guided to the V-grooves 121 of the pair of V-grooved stands 102A and 102B connected to the tips moves substantially in parallel. Further, the right and left elastic members 103A and 103B are disposed so as to be orthogonal to each other, and therefore, the movements in the X direction and the Y direction of the pair of optical fibers 90A and 90B as shown in FIG. 3 are also orthogonal to each other.
Then, in the fusion splicer 101 shown in FIGS. 9 and 10, the alignment of the tips 91a of the pair of optical fibers 90A and 90B shown in FIG. 3 is performed by finely moving the V-grooves 121 provided in the V-grooved stands 102A and 102B by elastically deforming the pair of elastic members 103A and 103B by respectively pressing the pair of V-grooved stands 102A and 102B by a pair of micrometers 105A and 105B. Further, in the fusion splicer 101 of the related art shown in FIGS. 9 and 10, a configuration is made such that a distance A between connection portions of the pair of elastic members 103A and 103B to the V-grooved stands 102A and 102B is narrower than a distance B between connection portions of the pair of elastic members 103A and 103B to the fixed base 104. Here, in FIG. 10, each of the distances A and B indicates, in the pair of elastic members 103A and 103B each having two plate-shaped members provided parallel to each other, a distance between the intermediate positions between joined portions of the two plate-shaped members.
Here, as a structure to align the tips of a pair of optical fibers in fusion-splicing the tips, a fusion splicer as described in Japanese Unexamined Utility Model Application, First Publication No. S58-67306 is proposed. In an elastic alignment mechanism described in the above publication, right and left elastic members each made of one piece are disposed in directions orthogonal to each other. Further, in the above publication, a configuration is made in which the distance between connection base portions of the elastic members to V-grooved stands is narrower than the distance between connection base portions of the elastic members to an L-shaped fixed base.
Further, as a structure to align the tips of a pair of optical fibers, a fusion splicer as described in Japanese Unexamined Patent Application, First Publication No. S63-108307 is proposed. An elastic alignment mechanism described in the above publication has a configuration in which the distance between connection portions of elastic members to a fixed base is larger than the distance between connection portions of the elastic members to V-grooved stands.
In addition, as a structure to align the tips of a pair of optical fibers, a fusion splicer as described in Japanese Unexamined Patent Application, First Publication No. H08-62446 is proposed. In an elastic alignment mechanism described in the above publication, right and left elastic members each made of one piece are disposed in directions orthogonal to each other. Further, in the above publication, a configuration is made in which the distance between connection portions of the elastic members to V-grooved stands is narrower than the distance between connection portions of the elastic members to a fixed base.
However, in the fusion splicer 101 of the related art as shown in FIGS. 9 and 10, for example, when the elastic members 103A are deformed by pressing by the micrometer 105A, since the distance B between the connection portions of the pair of elastic members 103A and 103B to the fixed base 104 is large, if the rigidity of the fixed base 104 made of a resin molding product or the like is low, distortion occurs in the fixed base 104, and thus there is a concern that the elastic alignment mechanism may break down or alignment accuracy may be reduced.
In addition, also in the fusion splicer which is provided with the elastic alignment mechanism described in each of Japanese Unexamined Utility Model Application, First Publication No. S58-67306, Japanese Unexamined Patent Application, First Publication No. S63-108307, and Japanese Unexamined Patent Application, First Publication No. H08-62446, similar to the above, the distance between the connection portions of the elastic members to the fixed base is large, and therefore, in a case where the rigidity of the fixed base is low, the same problem occurs.
Moreover, in the case of the fusion splicer 101 shown in FIGS. 9 and 10, as described above, the distance B between the connection portions of the pair of elastic members 103A and 103B to the fixed base 104 is larger than the distance A between the connection portions of the pair of elastic members 103A and 103B to the V-grooved stands 102A and 102B, and therefore, there is a problem in that the size of the fixed base 104 is increased and the weight is also increased. Further, also in the fusion splicer described in each of Japanese Unexamined Utility Model Application, First Publication No. S58-67306, Japanese Unexamined Patent Application, First Publication No. S63-108307, and Japanese Unexamined Patent Application, First Publication No. H08-62446, similar to the above, the distance between the connection portions of the elastic members to the fixed base is large, and therefore, there is the same problem in that the size of the fixed base 104 is increased and the weight is also increased.
Furthermore, in the fusion splicer 101 shown in FIGS. 9 and 10, in order to avoid lenses for observation 109 (not shown) which are disposed in the front and the back of the fusion splicer 101, and guides (not shown) which are disposed in a pair on the right and left sides, whereby the fiber clamps 106A and 106B (refer to FIG. 8) are driven forward, the pair of V-grooved stands 102A and 102B is configured so as to extend up and down (refer to a height C shown in FIG. 9), and the elastic members 103A and 103B are provided to extend toward the fixed base 104 from the V-grooved stands 102A and 102B. For this reason, in the fusion splicer of the related art, there is a problem in that the height of the entire mechanism is increased. Further, also in the fusion splicer described in Japanese Unexamined Patent Application, First Publication No. H08-62446, the elastic member on one side is disposed just below the V-grooved stand, and therefore, similar to the above, there is a problem in that the height of the entire mechanism is increased.
In addition, in the configuration of the fusion splicer of the related art, the connection portions of the elastic members 103A and 103B to the V-grooved stands 102A and 102B are disposed in the vicinity of a fusion splicing portion between the optical fibers, and therefore, there is a case where the pair of elastic members 103A and 103B interferes with the pair of fiber clamps 106A and 106B (refer to FIG. 8) or drive stages (not shown) for driving forward the fiber clamps 106A and 106B. In order to avoid such interference, it is necessary to dispose the V-grooves 121 on the upper side and dispose the elastic members 103A and 103B on the lower side of an apparatus. For this reason, a drive mechanism such as the micrometer 105A for elastically deforming the pair of elastic members 103A and 103B is disposed on the lower side of the apparatus, and therefore, there is a problem in that it is difficult to perform maintenance work from above the apparatus.
The present invention has been made in view of the above circumstances and provides an optical fiber fusion splicer in which it is possible to reduce the size and the weight of the entire elastic alignment mechanism such as a V-grooved stand or a fixed base while suppressing occurrence of distortion in the fixed base to which an elastic member is connected, and maintenance work is easy, and an optical fiber fusion splicing apparatus using the optical fiber fusion splicer.